The Senate will be asked to refer the election of One Nation senator Rod Culleton to the High Court.
Attorney-General George Brandis said in a statement on Wednesday the court would be asked to determine whether the West Australian senator was eligible for election because a larceny conviction stood at the time of the federal poll.
The Senate is already poised to refer former senator Bob Day to the High Court over a separate issue, which could potentially make it harder for the government to pass laws.
Senator Brandis said he had written to the Senate President Stephen Parry after receiving advice from the solicitor-general on October 28 concerning the election of Senator Culleton.
The opinion had been sought on October 13 after a former Culleton associate, Bruce Bell, petitioned the High Court to disqualify the WA senator over a larceny conviction in NSW.
The conviction - over a $7.50 key he took from a tow truck driver who was trying to repossess a lease car - has since been annulled.
Under the constitution, any person who has been convicted of an offence punishable by a jail sentence of a year or longer is incapable of being chosen as a senator.
Senator Brandis said the issue would come before the Senate on Monday.
"At that time, the government will initiate a referral of the matter to the High Court," he said.
'A dark cloud'
In a statement, Senator Culleton has lamented that this matter being made public ahead of Monday's vote.
"I’m disappointed it was leaked by a high level of Parliament before the matter could be dealt with correctly by the Senate,” he said.
He said it might see him not voting on any bills while the matter is investigated.
“While I have a dark cloud over me I have to remain honourable not only to myself, but to the Senate and to Parliament,” he said.
“A single action over a $7.50 key could now lead to an entire nation being stopped."
